2190 TEP is a hydrotreated heavy paraffinic distillate that may have been further refined by severe solvent extraction, severe hydrocracking, or severe hydrotreating (Chevron 2001). It is described as a clear colorless to pale yellow liquid. Few physical and chemical property data are available; however, Table 8-1 provides information from material-safety data sheets provided by Navy suppliers.

Mineral oil of inhalable particle size is called oil mist. The size of the particles depends on the process by which they are generated. Oil mists can potentially be generated in a variety of applications, which include metalworking, textile machinery, mist lubrication, and machining processes (ACGIH 2003; CONCAWE 1986). In submarines, generation of oil mist occurs primarily in the engine room. Inhalation and dermal contact are two possible exposure routes. The focus of this review is inhalation because adverse health effects resulting from dermal exposure are considered minimal provided that adequate personal-hygiene measures, such as wearing protective clothing and washing hands, are followed. Dermal toxicity of highly refined oils in humans is briefly summarized in CONCAWE (1986) and consists primarily of dermatitis and acne induced by oil.